SU1222710A1 - Line for hot-dip aluminizing of articles - Google Patents

Description

The invention relates to equipment for applying protective coatings to articles, in particular for hot aluminizing.

The aim of the invention is to improve the quality of products.

FIG. 1 shows the hot aluminization line of the products in FIG. 2, the same, top view; Fig, Zi 4 - thermal shock chamber with

The hot aluminizing line contains a thermal degreasing furnace 1 with an inlet conveyor 2. Adjacent to it is a thermal shock chamber 3, followed by a moisture removal chamber 4, a shot blasting chamber 5 and a drying chamber 6 connected by means of roller tables 7. Behind the dedusting chamber 6 Roller table-NB is placed: support 8 and device 9 is installed below it to detect surface cleaning defects.

The shot blasting chamber 5 is adjacent to the shot blasting chamber .10, which has a common ventilation system 11. Parallel to the main line, there is a monorail 12 for feeding the products rejected by the device 9 to the shot blasting chamber 10, which serves for additional surface cleaning.

Behind the dedusting chamber 6, the flux bath 13 and the preheating furnace 14 with the inlet roller table 15 are placed in series. The flux bath 13 is equipped with a tap 16.

Behind the flux bath is an aluminization bath 17. A portal installation 18 with a vibration device (not shown) is mounted above it.

A finishing station is located behind the aluminous bath. It includes a blowing chamber 19, a passivation bath 20 and an oil impregnation device 21, which is insulated in the form of a bath.

The thermal shock chamber is a rectangular chamber with a sheet of sheet material 22. In the opposite walls there are holes 23 through which a roller conveyor 24 is passed for installation of equipment 25 with products. Windows are closed with a cut with new shuttles F 26 for lsk, 1 spraying splashes into the room

227102

workshops. In the chamber 3, install piping 27 with nozzles 28 connected by means of high-pressure pumps 23 to a water supply system.

i; (not shown). The chamber is made with a water purification system and recirculation, including filters 30, blocking the openings in the cone-shaped bottom 31 and return pipe 32.

0 In the lower part of chamber 3, a magnetic belt conveyor 33 is installed to remove sludge from the chamber and a sludge collector 34 through a window 35 in the wall 22. To tension and adjust the belt | 5 of the conveyor 33, a tension section 36 is installed on the opposite wall of the chamber.

The line of hot aluminization works as follows.

20 The welded assemblies to be processed laid on special pallets are installed on the input conveyor 2 of the thermal degreasing furnace 1 and fed to the furnace where it is heated to

 300-350 ° C for full burnout of oil contaminants. After that, the pallets 22 with the products are fed to the roller conveyor 24 of the chamber 3, where they are fed under pressure from

sn snooled cold water, creating a thermal shock. Due to the difference in the coefficient of tert-expansion of scale and pure iron, the main part of the scale is separated from the product and falls to the bottom of the bath. It also reduces the cohesion between the remaining part of the scale and the product, which also creates favorable conditions for its complete separation during subsequent processing. The BinaM that has fallen to the bottom of the bath is removed from the chamber by a magnetic belt conveyor 33 and enters the collector 35.

After the thermal shock chamber, the trays with the products enter the moisture removal chamber 4, where the products are blown with dry air. The dried products enter the shot blasting chamber 5, where mechanical cleaning of the product surface and complete descaling is performed. After the shot blasting chamber 5, the products on the pallets fall into the dedusting chamber 6 J where they are cleaned of dust and

55 remove residual fractions. The product is then fed to the live-storage tank 8 and passes through the control device — the device 9 — to detect

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surface cleaning defects. The rejected products on the monorail 11 are transported to the shot-blasting chamber 5, where the products are completely cleaned, after that they return to the monorail 11 and the roller conveyor 8,

Quality products with a crane 16 together with a pallet are immersed in a flux bath 13} and transferred after being removed to a live conveyor 15 which is transported to a preheating furnace 14, where the products are heated to 200-300 ° C. After leaving the preheating furnace 14, the pallets with items are picked up by the hook of the portal unit 18 with a vibrating device and lowered into the aluminization bath 17, after which the vibrating device is switched to another mode and the excess coating is removed above the bath mirror. Other products are transferred by portal installation 18 into the blowing chamber 19, where they are cooled to 400-600 ° C, and then dipped into the passivation bath 20.

Passivation is carried out in a solution of chromic anhydride. As a result, 22710 4

, t on the surface of the product is formed of a passive film, giving it corrosion resistance. However, since the passive film has a varied structure, aggressive solutions can penetrate it and have a damaging effect on the product.

To avoid this, products after passivation are fed to the oil impregnator 21. The oil fills the smallest pores of the coating, as a result, the corrosion resistance of the product in aggressive environments is sharp

15 increases. In addition, an oil impregnator allows a softer cooling mode.

The advantage of the proposed line over the known ones is

20 in that it allows not only individual structural elements to be aluminized, but also welded units and to obtain a high-quality coating. This is because

25, the proposed line provides a high degree of purification of the products before aluminization and high-quality processing after coating, carried out on an optimal pressure.

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FIE

Editor A. Shandor

Compiled by A.P. Tibratov Tehred N. Bunkalo

Order 1672/26 Circulation 878 Subscription

VNIIPI USSR State Committee on Inventions and Discoveries 4/3, Moscow, Zh-35, Raushsk nab. 113035

Branch GShP Patent, Uzhgorod, st. Project, 4

Proofreader L. Patay

Claims (3)

1. A LINE OF HOT ALUMINATION OF PRODUCTS, mainly welded assemblies, containing a thermal degreasing furnace, a shot blasting chamber, a dust removal chamber, fluxing and aluminizing baths, a gantry unit with a vibrating device, a finishing section, transporting mechanisms, characterized in that, in order to improve the quality of products, fiG.1 it is equipped with a thermal shock chamber located behind the thermal degreasing furnace, and the final processing section flax in the form of a blower chamber, passivation bathtub and oil impregnation device. 2. The line according to claim 1, characterized in that the thermal shock chamber is equipped with a roller conveyor passing through windows in the side walls, pipelines with nozzles for supplying water, a high pressure pump with a water purification and recycling system, and a magnetic tape conveyor for removing sludge, at the bottom of the camera. 3. The line along π. 1, characterized in that it is equipped with a device for detecting surface cleaning defects and a storage roll installed behind the dedusting chamber, an additional shot blasting chamber connected to the storage roll by a monorail, the shot blasting chamber and the shot blasting chamber having a common ventilation system. Οϊδζζζι ¹ 1